Chlamydial antibodies in farmers in north-west England

Because of recent reports of abortion in farmers' wives following infection with ovine strains of Chlamydia psittaci during pregnancy, the distribution of chlamydial antibodies was studied in rural populations in north-west England, where endemic chlamydial infection with abortion is common in sheep. Immunoperoxidase assays with C. trachomatis and ovine C. psittaci showed no significant differences in either the frequency or titres of antibodies between sheep farmers and other types of farmer or non-farming adults living in the same areas. The frequency and titres of antibodies in farmers' wives were no greater than in farmers, and were unrelated to their previous obstetric history or type of farming. Overall, 62/255 (24%) of this rural population had antibody detected by C. trachomatis antigen and only 30/255 (13%) detected by C. psittaci antigen. The possible significance of these findings is discussed. This survey does not suggest that the risk of infection with C. psittaci is especially high in people working with sheep, but the complications following infection during pregnancy deserve the specific instructions that have been given to pregnant women to avoid exposure, especially during lambing, in farming and veterinary work.